A European research team reported insect biomass had decreased by about 75% over a 27-year study period.
The Study published in 2017, observed the trends in the population of flying insects in selected areas within agricultural landscapes over the last 27 years and concluded that climate change and habitat are to blame for the decline in insect populations.
The particular reason for the decline was not known, it could be climate change, improper land use and light pollution. To confirm the reason, research was carried out by scientists from the Light Pollution and Ecophysiology research group at IGB, Berlin. From the previous studies, the researchers confirmed that artificial lighting at night affects the number of insects.
The research team studied the locations involved in the 2017 study. These areas have high levels of light pollution. The research team recently published their work in Annals of Applied Biology. According to the study, light pollution affects insect population and diversity.
Most of the insect species are nocturnal. As such, they depend on darkness and natural light from the moon and stars for their movements. The natural light is enough for them to go about their nightly tasks of seeking food and reproducing.
Artificial lightings disturb their natural behaviour. It has a negative impact on their chances of survival in the night. These impacts are not only for the insects but also for plants. A decline in insect does not only mean a decline in species diversity but also jeopardises important ecosystem services: for example, there are then fewer moths, beetles and flies to pollinate plants.
Light pollution changes the distribution of pests such as aphids or their enemies such as beetles and spiders. This would disturb the eco-balance and diversity of insects.
It is high time that we consider Light pollution a potential ecosystem disturbance. In future, more studies should be done on measures to reduce environmental issues caused by light pollution.